Polyembryony, Biology

Assignment Help:

Polyembryony

Presence of more than one embryo in a seed is termed polyembryony. The phenomenon, first discovered in orange seeds by Leeuwenhoek (1719), attracted considerable attention because of its potential for application in and horticulture. Polyembryony is broadly classified into simple and multiple, depending on whether the supernumerary arises in one or more embryo sacs in the ovule. Simple polyembryony may be sexual or asexual. In sexual polyembryony embryos may originate from the fertilized egg and synergids, or by budding or cleavage of the polyembryony cells or suspensor of the zygotic embryo.

Asexual embryos are produced within the embryo sac without fertilization. Embryos may also originate from diploid nucellar or integumentary cells of the ode and grow into the embryo sac. These embryos are termed adventive or sporophytic. Multiple polyembryonies involve production of accessory embryos from two or more embryo sacs in the same ovule. For example, in the sea Island cotton, Gossypium barbadense, fertilization of egg in one embryo sac stimulates the induction of embryo from an unfertilized egg in the adjacent embryo sac within the same ovule. Thus, diploid-haploid twin embryos are produced in the seed.


Related Discussions:- Polyembryony

Explain solid salt and saturated aqueous solution, Explain solid salt and s...

Explain solid salt and saturated aqueous solution? In this example, the equilibrium system consists of crystalline PbCl 2 and an aqueous phase containing the species H 2 O, P

Alive and something that is a living organism, Is there a difference betwee...

Is there a difference between something that is alive and something that is a living organism?

Mechanism of enzyme action, Mechanism  of Enzyme Action  The action of...

Mechanism  of Enzyme Action  The action of enzymes is to lower  the activation energy  or threshold  of their substrates which. Therefore  become  activated and   react  with

Life cycle of malarial parasite, Life cycle of malarial parasite Whe...

Life cycle of malarial parasite When the mosquito sucks the blood, gametocytes enter its digestive system. They migrate into the walls of the digestive system and undergo

What are sarcomeres, What are sarcomeres? Sarcomeres are the contractil...

What are sarcomeres? Sarcomeres are the contractile units of the muscle tissue formed of alternating actin blocks (thin filaments) and myosin blocks (thick filaments). Various

importance of water in the body, Importance of water in the body Wa...

Importance of water in the body Water is the most essential constituent of life. Life cannot exist without water. About 90% of water is present in protoplasm  Water

Explain transfer from solid culture to liquid media, Explain Transfer from ...

Explain Transfer from Solid Culture to Liquid Media The steps involved in this technique are included herewith: 1. Sterilized inoculating loop or needle is touched carefully

Tissue culture, Note on production of haploid by tissue culture.

Note on production of haploid by tissue culture.

What are some factors that can lead to protein denaturizing, Protein denatu...

Protein denaturizing can be source by temperature variation, pH change, and changes in the concentration of surrounding solutes and by other processes. Most proteins are denatured

Procedures for diagnosis - advanced vaccine technology, A d v a ...

A d v a nce d vaccine technology: Genetic engineering technology is the major scientific revolution of 20th Century. This has helped in developing vaccine

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd